Electrochemical fabrication of TiO_2 nanoparticles/[BMIM]BF_4 ionic liquid hybrid film electrode and its application in determination of p-acetaminophen

摘要

A water soluble ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate (|BMIM]BF_4), was incorporated into TiO_2 nanoparticles to fabricate a hybrid film modified glassy carbon electrode (nano-TiO_2/|BMIM]BF_4/ GCE) through electrochemical deposition in a tetrabutyltitanate sol solution containing [BMIM]BF_4 The obtained nano-TiO_2/[BMIM]BF_4/GCEs were characterized scanning electronic microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Electrochemical behaviors of p-acetaminophen at the nano-TiO_2/[BMIM] BF_4/GCES were thoroughly investigated. Compared to the redox reaction of p-acetaminophen using an unmodified electrode under the same conditions, a new reduction peak was observed clearly at 0.26V with the modified electrode. In addition, the peak potential for the oxidation of p-acetaminophen was found to shift negatively about 90 mV and the current response increased significantly. These changes indicate that the nano-TiO_2/[BMIM]BF_4 hybrid film can improve the redox reactions of p-acetaminophen in aqueous medium. Under optimum conditions, a linear relationship was obtained for the p-acetaminophen solutions with concentration in the range from 5.0×10~(-8) to 5.0×10~(-5)M. The estimated detection limit was 1.0×10~(-8)M (S/N=3). The newly developed method was applied for the determination of p-acetaminophen in urine samples.